xref: /openbmc/linux/drivers/usb/chipidea/udc.c (revision 4f6cce39)
1 /*
2  * udc.c - ChipIdea UDC driver
3  *
4  * Copyright (C) 2008 Chipidea - MIPS Technologies, Inc. All rights reserved.
5  *
6  * Author: David Lopo
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  */
12 
13 #include <linux/delay.h>
14 #include <linux/device.h>
15 #include <linux/dmapool.h>
16 #include <linux/err.h>
17 #include <linux/irqreturn.h>
18 #include <linux/kernel.h>
19 #include <linux/slab.h>
20 #include <linux/pm_runtime.h>
21 #include <linux/usb/ch9.h>
22 #include <linux/usb/gadget.h>
23 #include <linux/usb/otg-fsm.h>
24 #include <linux/usb/chipidea.h>
25 
26 #include "ci.h"
27 #include "udc.h"
28 #include "bits.h"
29 #include "otg.h"
30 #include "otg_fsm.h"
31 
32 /* control endpoint description */
33 static const struct usb_endpoint_descriptor
34 ctrl_endpt_out_desc = {
35 	.bLength         = USB_DT_ENDPOINT_SIZE,
36 	.bDescriptorType = USB_DT_ENDPOINT,
37 
38 	.bEndpointAddress = USB_DIR_OUT,
39 	.bmAttributes    = USB_ENDPOINT_XFER_CONTROL,
40 	.wMaxPacketSize  = cpu_to_le16(CTRL_PAYLOAD_MAX),
41 };
42 
43 static const struct usb_endpoint_descriptor
44 ctrl_endpt_in_desc = {
45 	.bLength         = USB_DT_ENDPOINT_SIZE,
46 	.bDescriptorType = USB_DT_ENDPOINT,
47 
48 	.bEndpointAddress = USB_DIR_IN,
49 	.bmAttributes    = USB_ENDPOINT_XFER_CONTROL,
50 	.wMaxPacketSize  = cpu_to_le16(CTRL_PAYLOAD_MAX),
51 };
52 
53 /**
54  * hw_ep_bit: calculates the bit number
55  * @num: endpoint number
56  * @dir: endpoint direction
57  *
58  * This function returns bit number
59  */
60 static inline int hw_ep_bit(int num, int dir)
61 {
62 	return num + ((dir == TX) ? 16 : 0);
63 }
64 
65 static inline int ep_to_bit(struct ci_hdrc *ci, int n)
66 {
67 	int fill = 16 - ci->hw_ep_max / 2;
68 
69 	if (n >= ci->hw_ep_max / 2)
70 		n += fill;
71 
72 	return n;
73 }
74 
75 /**
76  * hw_device_state: enables/disables interrupts (execute without interruption)
77  * @dma: 0 => disable, !0 => enable and set dma engine
78  *
79  * This function returns an error code
80  */
81 static int hw_device_state(struct ci_hdrc *ci, u32 dma)
82 {
83 	if (dma) {
84 		hw_write(ci, OP_ENDPTLISTADDR, ~0, dma);
85 		/* interrupt, error, port change, reset, sleep/suspend */
86 		hw_write(ci, OP_USBINTR, ~0,
87 			     USBi_UI|USBi_UEI|USBi_PCI|USBi_URI|USBi_SLI);
88 	} else {
89 		hw_write(ci, OP_USBINTR, ~0, 0);
90 	}
91 	return 0;
92 }
93 
94 /**
95  * hw_ep_flush: flush endpoint fifo (execute without interruption)
96  * @num: endpoint number
97  * @dir: endpoint direction
98  *
99  * This function returns an error code
100  */
101 static int hw_ep_flush(struct ci_hdrc *ci, int num, int dir)
102 {
103 	int n = hw_ep_bit(num, dir);
104 
105 	do {
106 		/* flush any pending transfer */
107 		hw_write(ci, OP_ENDPTFLUSH, ~0, BIT(n));
108 		while (hw_read(ci, OP_ENDPTFLUSH, BIT(n)))
109 			cpu_relax();
110 	} while (hw_read(ci, OP_ENDPTSTAT, BIT(n)));
111 
112 	return 0;
113 }
114 
115 /**
116  * hw_ep_disable: disables endpoint (execute without interruption)
117  * @num: endpoint number
118  * @dir: endpoint direction
119  *
120  * This function returns an error code
121  */
122 static int hw_ep_disable(struct ci_hdrc *ci, int num, int dir)
123 {
124 	hw_write(ci, OP_ENDPTCTRL + num,
125 		 (dir == TX) ? ENDPTCTRL_TXE : ENDPTCTRL_RXE, 0);
126 	return 0;
127 }
128 
129 /**
130  * hw_ep_enable: enables endpoint (execute without interruption)
131  * @num:  endpoint number
132  * @dir:  endpoint direction
133  * @type: endpoint type
134  *
135  * This function returns an error code
136  */
137 static int hw_ep_enable(struct ci_hdrc *ci, int num, int dir, int type)
138 {
139 	u32 mask, data;
140 
141 	if (dir == TX) {
142 		mask  = ENDPTCTRL_TXT;  /* type    */
143 		data  = type << __ffs(mask);
144 
145 		mask |= ENDPTCTRL_TXS;  /* unstall */
146 		mask |= ENDPTCTRL_TXR;  /* reset data toggle */
147 		data |= ENDPTCTRL_TXR;
148 		mask |= ENDPTCTRL_TXE;  /* enable  */
149 		data |= ENDPTCTRL_TXE;
150 	} else {
151 		mask  = ENDPTCTRL_RXT;  /* type    */
152 		data  = type << __ffs(mask);
153 
154 		mask |= ENDPTCTRL_RXS;  /* unstall */
155 		mask |= ENDPTCTRL_RXR;  /* reset data toggle */
156 		data |= ENDPTCTRL_RXR;
157 		mask |= ENDPTCTRL_RXE;  /* enable  */
158 		data |= ENDPTCTRL_RXE;
159 	}
160 	hw_write(ci, OP_ENDPTCTRL + num, mask, data);
161 	return 0;
162 }
163 
164 /**
165  * hw_ep_get_halt: return endpoint halt status
166  * @num: endpoint number
167  * @dir: endpoint direction
168  *
169  * This function returns 1 if endpoint halted
170  */
171 static int hw_ep_get_halt(struct ci_hdrc *ci, int num, int dir)
172 {
173 	u32 mask = (dir == TX) ? ENDPTCTRL_TXS : ENDPTCTRL_RXS;
174 
175 	return hw_read(ci, OP_ENDPTCTRL + num, mask) ? 1 : 0;
176 }
177 
178 /**
179  * hw_ep_prime: primes endpoint (execute without interruption)
180  * @num:     endpoint number
181  * @dir:     endpoint direction
182  * @is_ctrl: true if control endpoint
183  *
184  * This function returns an error code
185  */
186 static int hw_ep_prime(struct ci_hdrc *ci, int num, int dir, int is_ctrl)
187 {
188 	int n = hw_ep_bit(num, dir);
189 
190 	/* Synchronize before ep prime */
191 	wmb();
192 
193 	if (is_ctrl && dir == RX && hw_read(ci, OP_ENDPTSETUPSTAT, BIT(num)))
194 		return -EAGAIN;
195 
196 	hw_write(ci, OP_ENDPTPRIME, ~0, BIT(n));
197 
198 	while (hw_read(ci, OP_ENDPTPRIME, BIT(n)))
199 		cpu_relax();
200 	if (is_ctrl && dir == RX && hw_read(ci, OP_ENDPTSETUPSTAT, BIT(num)))
201 		return -EAGAIN;
202 
203 	/* status shoult be tested according with manual but it doesn't work */
204 	return 0;
205 }
206 
207 /**
208  * hw_ep_set_halt: configures ep halt & resets data toggle after clear (execute
209  *                 without interruption)
210  * @num:   endpoint number
211  * @dir:   endpoint direction
212  * @value: true => stall, false => unstall
213  *
214  * This function returns an error code
215  */
216 static int hw_ep_set_halt(struct ci_hdrc *ci, int num, int dir, int value)
217 {
218 	if (value != 0 && value != 1)
219 		return -EINVAL;
220 
221 	do {
222 		enum ci_hw_regs reg = OP_ENDPTCTRL + num;
223 		u32 mask_xs = (dir == TX) ? ENDPTCTRL_TXS : ENDPTCTRL_RXS;
224 		u32 mask_xr = (dir == TX) ? ENDPTCTRL_TXR : ENDPTCTRL_RXR;
225 
226 		/* data toggle - reserved for EP0 but it's in ESS */
227 		hw_write(ci, reg, mask_xs|mask_xr,
228 			  value ? mask_xs : mask_xr);
229 	} while (value != hw_ep_get_halt(ci, num, dir));
230 
231 	return 0;
232 }
233 
234 /**
235  * hw_is_port_high_speed: test if port is high speed
236  *
237  * This function returns true if high speed port
238  */
239 static int hw_port_is_high_speed(struct ci_hdrc *ci)
240 {
241 	return ci->hw_bank.lpm ? hw_read(ci, OP_DEVLC, DEVLC_PSPD) :
242 		hw_read(ci, OP_PORTSC, PORTSC_HSP);
243 }
244 
245 /**
246  * hw_test_and_clear_complete: test & clear complete status (execute without
247  *                             interruption)
248  * @n: endpoint number
249  *
250  * This function returns complete status
251  */
252 static int hw_test_and_clear_complete(struct ci_hdrc *ci, int n)
253 {
254 	n = ep_to_bit(ci, n);
255 	return hw_test_and_clear(ci, OP_ENDPTCOMPLETE, BIT(n));
256 }
257 
258 /**
259  * hw_test_and_clear_intr_active: test & clear active interrupts (execute
260  *                                without interruption)
261  *
262  * This function returns active interrutps
263  */
264 static u32 hw_test_and_clear_intr_active(struct ci_hdrc *ci)
265 {
266 	u32 reg = hw_read_intr_status(ci) & hw_read_intr_enable(ci);
267 
268 	hw_write(ci, OP_USBSTS, ~0, reg);
269 	return reg;
270 }
271 
272 /**
273  * hw_test_and_clear_setup_guard: test & clear setup guard (execute without
274  *                                interruption)
275  *
276  * This function returns guard value
277  */
278 static int hw_test_and_clear_setup_guard(struct ci_hdrc *ci)
279 {
280 	return hw_test_and_write(ci, OP_USBCMD, USBCMD_SUTW, 0);
281 }
282 
283 /**
284  * hw_test_and_set_setup_guard: test & set setup guard (execute without
285  *                              interruption)
286  *
287  * This function returns guard value
288  */
289 static int hw_test_and_set_setup_guard(struct ci_hdrc *ci)
290 {
291 	return hw_test_and_write(ci, OP_USBCMD, USBCMD_SUTW, USBCMD_SUTW);
292 }
293 
294 /**
295  * hw_usb_set_address: configures USB address (execute without interruption)
296  * @value: new USB address
297  *
298  * This function explicitly sets the address, without the "USBADRA" (advance)
299  * feature, which is not supported by older versions of the controller.
300  */
301 static void hw_usb_set_address(struct ci_hdrc *ci, u8 value)
302 {
303 	hw_write(ci, OP_DEVICEADDR, DEVICEADDR_USBADR,
304 		 value << __ffs(DEVICEADDR_USBADR));
305 }
306 
307 /**
308  * hw_usb_reset: restart device after a bus reset (execute without
309  *               interruption)
310  *
311  * This function returns an error code
312  */
313 static int hw_usb_reset(struct ci_hdrc *ci)
314 {
315 	hw_usb_set_address(ci, 0);
316 
317 	/* ESS flushes only at end?!? */
318 	hw_write(ci, OP_ENDPTFLUSH,    ~0, ~0);
319 
320 	/* clear setup token semaphores */
321 	hw_write(ci, OP_ENDPTSETUPSTAT, 0,  0);
322 
323 	/* clear complete status */
324 	hw_write(ci, OP_ENDPTCOMPLETE,  0,  0);
325 
326 	/* wait until all bits cleared */
327 	while (hw_read(ci, OP_ENDPTPRIME, ~0))
328 		udelay(10);             /* not RTOS friendly */
329 
330 	/* reset all endpoints ? */
331 
332 	/* reset internal status and wait for further instructions
333 	   no need to verify the port reset status (ESS does it) */
334 
335 	return 0;
336 }
337 
338 /******************************************************************************
339  * UTIL block
340  *****************************************************************************/
341 
342 static int add_td_to_list(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq,
343 			  unsigned length)
344 {
345 	int i;
346 	u32 temp;
347 	struct td_node *lastnode, *node = kzalloc(sizeof(struct td_node),
348 						  GFP_ATOMIC);
349 
350 	if (node == NULL)
351 		return -ENOMEM;
352 
353 	node->ptr = dma_pool_zalloc(hwep->td_pool, GFP_ATOMIC, &node->dma);
354 	if (node->ptr == NULL) {
355 		kfree(node);
356 		return -ENOMEM;
357 	}
358 
359 	node->ptr->token = cpu_to_le32(length << __ffs(TD_TOTAL_BYTES));
360 	node->ptr->token &= cpu_to_le32(TD_TOTAL_BYTES);
361 	node->ptr->token |= cpu_to_le32(TD_STATUS_ACTIVE);
362 	if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == TX) {
363 		u32 mul = hwreq->req.length / hwep->ep.maxpacket;
364 
365 		if (hwreq->req.length == 0
366 				|| hwreq->req.length % hwep->ep.maxpacket)
367 			mul++;
368 		node->ptr->token |= cpu_to_le32(mul << __ffs(TD_MULTO));
369 	}
370 
371 	temp = (u32) (hwreq->req.dma + hwreq->req.actual);
372 	if (length) {
373 		node->ptr->page[0] = cpu_to_le32(temp);
374 		for (i = 1; i < TD_PAGE_COUNT; i++) {
375 			u32 page = temp + i * CI_HDRC_PAGE_SIZE;
376 			page &= ~TD_RESERVED_MASK;
377 			node->ptr->page[i] = cpu_to_le32(page);
378 		}
379 	}
380 
381 	hwreq->req.actual += length;
382 
383 	if (!list_empty(&hwreq->tds)) {
384 		/* get the last entry */
385 		lastnode = list_entry(hwreq->tds.prev,
386 				struct td_node, td);
387 		lastnode->ptr->next = cpu_to_le32(node->dma);
388 	}
389 
390 	INIT_LIST_HEAD(&node->td);
391 	list_add_tail(&node->td, &hwreq->tds);
392 
393 	return 0;
394 }
395 
396 /**
397  * _usb_addr: calculates endpoint address from direction & number
398  * @ep:  endpoint
399  */
400 static inline u8 _usb_addr(struct ci_hw_ep *ep)
401 {
402 	return ((ep->dir == TX) ? USB_ENDPOINT_DIR_MASK : 0) | ep->num;
403 }
404 
405 /**
406  * _hardware_enqueue: configures a request at hardware level
407  * @hwep:   endpoint
408  * @hwreq:  request
409  *
410  * This function returns an error code
411  */
412 static int _hardware_enqueue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
413 {
414 	struct ci_hdrc *ci = hwep->ci;
415 	int ret = 0;
416 	unsigned rest = hwreq->req.length;
417 	int pages = TD_PAGE_COUNT;
418 	struct td_node *firstnode, *lastnode;
419 
420 	/* don't queue twice */
421 	if (hwreq->req.status == -EALREADY)
422 		return -EALREADY;
423 
424 	hwreq->req.status = -EALREADY;
425 
426 	ret = usb_gadget_map_request(&ci->gadget, &hwreq->req, hwep->dir);
427 	if (ret)
428 		return ret;
429 
430 	/*
431 	 * The first buffer could be not page aligned.
432 	 * In that case we have to span into one extra td.
433 	 */
434 	if (hwreq->req.dma % PAGE_SIZE)
435 		pages--;
436 
437 	if (rest == 0) {
438 		ret = add_td_to_list(hwep, hwreq, 0);
439 		if (ret < 0)
440 			goto done;
441 	}
442 
443 	while (rest > 0) {
444 		unsigned count = min(hwreq->req.length - hwreq->req.actual,
445 					(unsigned)(pages * CI_HDRC_PAGE_SIZE));
446 		ret = add_td_to_list(hwep, hwreq, count);
447 		if (ret < 0)
448 			goto done;
449 
450 		rest -= count;
451 	}
452 
453 	if (hwreq->req.zero && hwreq->req.length && hwep->dir == TX
454 	    && (hwreq->req.length % hwep->ep.maxpacket == 0)) {
455 		ret = add_td_to_list(hwep, hwreq, 0);
456 		if (ret < 0)
457 			goto done;
458 	}
459 
460 	firstnode = list_first_entry(&hwreq->tds, struct td_node, td);
461 
462 	lastnode = list_entry(hwreq->tds.prev,
463 		struct td_node, td);
464 
465 	lastnode->ptr->next = cpu_to_le32(TD_TERMINATE);
466 	if (!hwreq->req.no_interrupt)
467 		lastnode->ptr->token |= cpu_to_le32(TD_IOC);
468 	wmb();
469 
470 	hwreq->req.actual = 0;
471 	if (!list_empty(&hwep->qh.queue)) {
472 		struct ci_hw_req *hwreqprev;
473 		int n = hw_ep_bit(hwep->num, hwep->dir);
474 		int tmp_stat;
475 		struct td_node *prevlastnode;
476 		u32 next = firstnode->dma & TD_ADDR_MASK;
477 
478 		hwreqprev = list_entry(hwep->qh.queue.prev,
479 				struct ci_hw_req, queue);
480 		prevlastnode = list_entry(hwreqprev->tds.prev,
481 				struct td_node, td);
482 
483 		prevlastnode->ptr->next = cpu_to_le32(next);
484 		wmb();
485 		if (hw_read(ci, OP_ENDPTPRIME, BIT(n)))
486 			goto done;
487 		do {
488 			hw_write(ci, OP_USBCMD, USBCMD_ATDTW, USBCMD_ATDTW);
489 			tmp_stat = hw_read(ci, OP_ENDPTSTAT, BIT(n));
490 		} while (!hw_read(ci, OP_USBCMD, USBCMD_ATDTW));
491 		hw_write(ci, OP_USBCMD, USBCMD_ATDTW, 0);
492 		if (tmp_stat)
493 			goto done;
494 	}
495 
496 	/*  QH configuration */
497 	hwep->qh.ptr->td.next = cpu_to_le32(firstnode->dma);
498 	hwep->qh.ptr->td.token &=
499 		cpu_to_le32(~(TD_STATUS_HALTED|TD_STATUS_ACTIVE));
500 
501 	if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == RX) {
502 		u32 mul = hwreq->req.length / hwep->ep.maxpacket;
503 
504 		if (hwreq->req.length == 0
505 				|| hwreq->req.length % hwep->ep.maxpacket)
506 			mul++;
507 		hwep->qh.ptr->cap |= cpu_to_le32(mul << __ffs(QH_MULT));
508 	}
509 
510 	ret = hw_ep_prime(ci, hwep->num, hwep->dir,
511 			   hwep->type == USB_ENDPOINT_XFER_CONTROL);
512 done:
513 	return ret;
514 }
515 
516 /*
517  * free_pending_td: remove a pending request for the endpoint
518  * @hwep: endpoint
519  */
520 static void free_pending_td(struct ci_hw_ep *hwep)
521 {
522 	struct td_node *pending = hwep->pending_td;
523 
524 	dma_pool_free(hwep->td_pool, pending->ptr, pending->dma);
525 	hwep->pending_td = NULL;
526 	kfree(pending);
527 }
528 
529 static int reprime_dtd(struct ci_hdrc *ci, struct ci_hw_ep *hwep,
530 					   struct td_node *node)
531 {
532 	hwep->qh.ptr->td.next = cpu_to_le32(node->dma);
533 	hwep->qh.ptr->td.token &=
534 		cpu_to_le32(~(TD_STATUS_HALTED | TD_STATUS_ACTIVE));
535 
536 	return hw_ep_prime(ci, hwep->num, hwep->dir,
537 				hwep->type == USB_ENDPOINT_XFER_CONTROL);
538 }
539 
540 /**
541  * _hardware_dequeue: handles a request at hardware level
542  * @gadget: gadget
543  * @hwep:   endpoint
544  *
545  * This function returns an error code
546  */
547 static int _hardware_dequeue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
548 {
549 	u32 tmptoken;
550 	struct td_node *node, *tmpnode;
551 	unsigned remaining_length;
552 	unsigned actual = hwreq->req.length;
553 	struct ci_hdrc *ci = hwep->ci;
554 
555 	if (hwreq->req.status != -EALREADY)
556 		return -EINVAL;
557 
558 	hwreq->req.status = 0;
559 
560 	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
561 		tmptoken = le32_to_cpu(node->ptr->token);
562 		if ((TD_STATUS_ACTIVE & tmptoken) != 0) {
563 			int n = hw_ep_bit(hwep->num, hwep->dir);
564 
565 			if (ci->rev == CI_REVISION_24)
566 				if (!hw_read(ci, OP_ENDPTSTAT, BIT(n)))
567 					reprime_dtd(ci, hwep, node);
568 			hwreq->req.status = -EALREADY;
569 			return -EBUSY;
570 		}
571 
572 		remaining_length = (tmptoken & TD_TOTAL_BYTES);
573 		remaining_length >>= __ffs(TD_TOTAL_BYTES);
574 		actual -= remaining_length;
575 
576 		hwreq->req.status = tmptoken & TD_STATUS;
577 		if ((TD_STATUS_HALTED & hwreq->req.status)) {
578 			hwreq->req.status = -EPIPE;
579 			break;
580 		} else if ((TD_STATUS_DT_ERR & hwreq->req.status)) {
581 			hwreq->req.status = -EPROTO;
582 			break;
583 		} else if ((TD_STATUS_TR_ERR & hwreq->req.status)) {
584 			hwreq->req.status = -EILSEQ;
585 			break;
586 		}
587 
588 		if (remaining_length) {
589 			if (hwep->dir == TX) {
590 				hwreq->req.status = -EPROTO;
591 				break;
592 			}
593 		}
594 		/*
595 		 * As the hardware could still address the freed td
596 		 * which will run the udc unusable, the cleanup of the
597 		 * td has to be delayed by one.
598 		 */
599 		if (hwep->pending_td)
600 			free_pending_td(hwep);
601 
602 		hwep->pending_td = node;
603 		list_del_init(&node->td);
604 	}
605 
606 	usb_gadget_unmap_request(&hwep->ci->gadget, &hwreq->req, hwep->dir);
607 
608 	hwreq->req.actual += actual;
609 
610 	if (hwreq->req.status)
611 		return hwreq->req.status;
612 
613 	return hwreq->req.actual;
614 }
615 
616 /**
617  * _ep_nuke: dequeues all endpoint requests
618  * @hwep: endpoint
619  *
620  * This function returns an error code
621  * Caller must hold lock
622  */
623 static int _ep_nuke(struct ci_hw_ep *hwep)
624 __releases(hwep->lock)
625 __acquires(hwep->lock)
626 {
627 	struct td_node *node, *tmpnode;
628 	if (hwep == NULL)
629 		return -EINVAL;
630 
631 	hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
632 
633 	while (!list_empty(&hwep->qh.queue)) {
634 
635 		/* pop oldest request */
636 		struct ci_hw_req *hwreq = list_entry(hwep->qh.queue.next,
637 						     struct ci_hw_req, queue);
638 
639 		list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
640 			dma_pool_free(hwep->td_pool, node->ptr, node->dma);
641 			list_del_init(&node->td);
642 			node->ptr = NULL;
643 			kfree(node);
644 		}
645 
646 		list_del_init(&hwreq->queue);
647 		hwreq->req.status = -ESHUTDOWN;
648 
649 		if (hwreq->req.complete != NULL) {
650 			spin_unlock(hwep->lock);
651 			usb_gadget_giveback_request(&hwep->ep, &hwreq->req);
652 			spin_lock(hwep->lock);
653 		}
654 	}
655 
656 	if (hwep->pending_td)
657 		free_pending_td(hwep);
658 
659 	return 0;
660 }
661 
662 static int _ep_set_halt(struct usb_ep *ep, int value, bool check_transfer)
663 {
664 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
665 	int direction, retval = 0;
666 	unsigned long flags;
667 
668 	if (ep == NULL || hwep->ep.desc == NULL)
669 		return -EINVAL;
670 
671 	if (usb_endpoint_xfer_isoc(hwep->ep.desc))
672 		return -EOPNOTSUPP;
673 
674 	spin_lock_irqsave(hwep->lock, flags);
675 
676 	if (value && hwep->dir == TX && check_transfer &&
677 		!list_empty(&hwep->qh.queue) &&
678 			!usb_endpoint_xfer_control(hwep->ep.desc)) {
679 		spin_unlock_irqrestore(hwep->lock, flags);
680 		return -EAGAIN;
681 	}
682 
683 	direction = hwep->dir;
684 	do {
685 		retval |= hw_ep_set_halt(hwep->ci, hwep->num, hwep->dir, value);
686 
687 		if (!value)
688 			hwep->wedge = 0;
689 
690 		if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
691 			hwep->dir = (hwep->dir == TX) ? RX : TX;
692 
693 	} while (hwep->dir != direction);
694 
695 	spin_unlock_irqrestore(hwep->lock, flags);
696 	return retval;
697 }
698 
699 
700 /**
701  * _gadget_stop_activity: stops all USB activity, flushes & disables all endpts
702  * @gadget: gadget
703  *
704  * This function returns an error code
705  */
706 static int _gadget_stop_activity(struct usb_gadget *gadget)
707 {
708 	struct usb_ep *ep;
709 	struct ci_hdrc    *ci = container_of(gadget, struct ci_hdrc, gadget);
710 	unsigned long flags;
711 
712 	spin_lock_irqsave(&ci->lock, flags);
713 	ci->gadget.speed = USB_SPEED_UNKNOWN;
714 	ci->remote_wakeup = 0;
715 	ci->suspended = 0;
716 	spin_unlock_irqrestore(&ci->lock, flags);
717 
718 	/* flush all endpoints */
719 	gadget_for_each_ep(ep, gadget) {
720 		usb_ep_fifo_flush(ep);
721 	}
722 	usb_ep_fifo_flush(&ci->ep0out->ep);
723 	usb_ep_fifo_flush(&ci->ep0in->ep);
724 
725 	/* make sure to disable all endpoints */
726 	gadget_for_each_ep(ep, gadget) {
727 		usb_ep_disable(ep);
728 	}
729 
730 	if (ci->status != NULL) {
731 		usb_ep_free_request(&ci->ep0in->ep, ci->status);
732 		ci->status = NULL;
733 	}
734 
735 	return 0;
736 }
737 
738 /******************************************************************************
739  * ISR block
740  *****************************************************************************/
741 /**
742  * isr_reset_handler: USB reset interrupt handler
743  * @ci: UDC device
744  *
745  * This function resets USB engine after a bus reset occurred
746  */
747 static void isr_reset_handler(struct ci_hdrc *ci)
748 __releases(ci->lock)
749 __acquires(ci->lock)
750 {
751 	int retval;
752 
753 	spin_unlock(&ci->lock);
754 	if (ci->gadget.speed != USB_SPEED_UNKNOWN)
755 		usb_gadget_udc_reset(&ci->gadget, ci->driver);
756 
757 	retval = _gadget_stop_activity(&ci->gadget);
758 	if (retval)
759 		goto done;
760 
761 	retval = hw_usb_reset(ci);
762 	if (retval)
763 		goto done;
764 
765 	ci->status = usb_ep_alloc_request(&ci->ep0in->ep, GFP_ATOMIC);
766 	if (ci->status == NULL)
767 		retval = -ENOMEM;
768 
769 done:
770 	spin_lock(&ci->lock);
771 
772 	if (retval)
773 		dev_err(ci->dev, "error: %i\n", retval);
774 }
775 
776 /**
777  * isr_get_status_complete: get_status request complete function
778  * @ep:  endpoint
779  * @req: request handled
780  *
781  * Caller must release lock
782  */
783 static void isr_get_status_complete(struct usb_ep *ep, struct usb_request *req)
784 {
785 	if (ep == NULL || req == NULL)
786 		return;
787 
788 	kfree(req->buf);
789 	usb_ep_free_request(ep, req);
790 }
791 
792 /**
793  * _ep_queue: queues (submits) an I/O request to an endpoint
794  * @ep:        endpoint
795  * @req:       request
796  * @gfp_flags: GFP flags (not used)
797  *
798  * Caller must hold lock
799  * This function returns an error code
800  */
801 static int _ep_queue(struct usb_ep *ep, struct usb_request *req,
802 		    gfp_t __maybe_unused gfp_flags)
803 {
804 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
805 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
806 	struct ci_hdrc *ci = hwep->ci;
807 	int retval = 0;
808 
809 	if (ep == NULL || req == NULL || hwep->ep.desc == NULL)
810 		return -EINVAL;
811 
812 	if (hwep->type == USB_ENDPOINT_XFER_CONTROL) {
813 		if (req->length)
814 			hwep = (ci->ep0_dir == RX) ?
815 			       ci->ep0out : ci->ep0in;
816 		if (!list_empty(&hwep->qh.queue)) {
817 			_ep_nuke(hwep);
818 			dev_warn(hwep->ci->dev, "endpoint ctrl %X nuked\n",
819 				 _usb_addr(hwep));
820 		}
821 	}
822 
823 	if (usb_endpoint_xfer_isoc(hwep->ep.desc) &&
824 	    hwreq->req.length > hwep->ep.mult * hwep->ep.maxpacket) {
825 		dev_err(hwep->ci->dev, "request length too big for isochronous\n");
826 		return -EMSGSIZE;
827 	}
828 
829 	/* first nuke then test link, e.g. previous status has not sent */
830 	if (!list_empty(&hwreq->queue)) {
831 		dev_err(hwep->ci->dev, "request already in queue\n");
832 		return -EBUSY;
833 	}
834 
835 	/* push request */
836 	hwreq->req.status = -EINPROGRESS;
837 	hwreq->req.actual = 0;
838 
839 	retval = _hardware_enqueue(hwep, hwreq);
840 
841 	if (retval == -EALREADY)
842 		retval = 0;
843 	if (!retval)
844 		list_add_tail(&hwreq->queue, &hwep->qh.queue);
845 
846 	return retval;
847 }
848 
849 /**
850  * isr_get_status_response: get_status request response
851  * @ci: ci struct
852  * @setup: setup request packet
853  *
854  * This function returns an error code
855  */
856 static int isr_get_status_response(struct ci_hdrc *ci,
857 				   struct usb_ctrlrequest *setup)
858 __releases(hwep->lock)
859 __acquires(hwep->lock)
860 {
861 	struct ci_hw_ep *hwep = ci->ep0in;
862 	struct usb_request *req = NULL;
863 	gfp_t gfp_flags = GFP_ATOMIC;
864 	int dir, num, retval;
865 
866 	if (hwep == NULL || setup == NULL)
867 		return -EINVAL;
868 
869 	spin_unlock(hwep->lock);
870 	req = usb_ep_alloc_request(&hwep->ep, gfp_flags);
871 	spin_lock(hwep->lock);
872 	if (req == NULL)
873 		return -ENOMEM;
874 
875 	req->complete = isr_get_status_complete;
876 	req->length   = 2;
877 	req->buf      = kzalloc(req->length, gfp_flags);
878 	if (req->buf == NULL) {
879 		retval = -ENOMEM;
880 		goto err_free_req;
881 	}
882 
883 	if ((setup->bRequestType & USB_RECIP_MASK) == USB_RECIP_DEVICE) {
884 		*(u16 *)req->buf = (ci->remote_wakeup << 1) |
885 			ci->gadget.is_selfpowered;
886 	} else if ((setup->bRequestType & USB_RECIP_MASK) \
887 		   == USB_RECIP_ENDPOINT) {
888 		dir = (le16_to_cpu(setup->wIndex) & USB_ENDPOINT_DIR_MASK) ?
889 			TX : RX;
890 		num =  le16_to_cpu(setup->wIndex) & USB_ENDPOINT_NUMBER_MASK;
891 		*(u16 *)req->buf = hw_ep_get_halt(ci, num, dir);
892 	}
893 	/* else do nothing; reserved for future use */
894 
895 	retval = _ep_queue(&hwep->ep, req, gfp_flags);
896 	if (retval)
897 		goto err_free_buf;
898 
899 	return 0;
900 
901  err_free_buf:
902 	kfree(req->buf);
903  err_free_req:
904 	spin_unlock(hwep->lock);
905 	usb_ep_free_request(&hwep->ep, req);
906 	spin_lock(hwep->lock);
907 	return retval;
908 }
909 
910 /**
911  * isr_setup_status_complete: setup_status request complete function
912  * @ep:  endpoint
913  * @req: request handled
914  *
915  * Caller must release lock. Put the port in test mode if test mode
916  * feature is selected.
917  */
918 static void
919 isr_setup_status_complete(struct usb_ep *ep, struct usb_request *req)
920 {
921 	struct ci_hdrc *ci = req->context;
922 	unsigned long flags;
923 
924 	if (ci->setaddr) {
925 		hw_usb_set_address(ci, ci->address);
926 		ci->setaddr = false;
927 		if (ci->address)
928 			usb_gadget_set_state(&ci->gadget, USB_STATE_ADDRESS);
929 	}
930 
931 	spin_lock_irqsave(&ci->lock, flags);
932 	if (ci->test_mode)
933 		hw_port_test_set(ci, ci->test_mode);
934 	spin_unlock_irqrestore(&ci->lock, flags);
935 }
936 
937 /**
938  * isr_setup_status_phase: queues the status phase of a setup transation
939  * @ci: ci struct
940  *
941  * This function returns an error code
942  */
943 static int isr_setup_status_phase(struct ci_hdrc *ci)
944 {
945 	int retval;
946 	struct ci_hw_ep *hwep;
947 
948 	/*
949 	 * Unexpected USB controller behavior, caused by bad signal integrity
950 	 * or ground reference problems, can lead to isr_setup_status_phase
951 	 * being called with ci->status equal to NULL.
952 	 * If this situation occurs, you should review your USB hardware design.
953 	 */
954 	if (WARN_ON_ONCE(!ci->status))
955 		return -EPIPE;
956 
957 	hwep = (ci->ep0_dir == TX) ? ci->ep0out : ci->ep0in;
958 	ci->status->context = ci;
959 	ci->status->complete = isr_setup_status_complete;
960 
961 	retval = _ep_queue(&hwep->ep, ci->status, GFP_ATOMIC);
962 
963 	return retval;
964 }
965 
966 /**
967  * isr_tr_complete_low: transaction complete low level handler
968  * @hwep: endpoint
969  *
970  * This function returns an error code
971  * Caller must hold lock
972  */
973 static int isr_tr_complete_low(struct ci_hw_ep *hwep)
974 __releases(hwep->lock)
975 __acquires(hwep->lock)
976 {
977 	struct ci_hw_req *hwreq, *hwreqtemp;
978 	struct ci_hw_ep *hweptemp = hwep;
979 	int retval = 0;
980 
981 	list_for_each_entry_safe(hwreq, hwreqtemp, &hwep->qh.queue,
982 			queue) {
983 		retval = _hardware_dequeue(hwep, hwreq);
984 		if (retval < 0)
985 			break;
986 		list_del_init(&hwreq->queue);
987 		if (hwreq->req.complete != NULL) {
988 			spin_unlock(hwep->lock);
989 			if ((hwep->type == USB_ENDPOINT_XFER_CONTROL) &&
990 					hwreq->req.length)
991 				hweptemp = hwep->ci->ep0in;
992 			usb_gadget_giveback_request(&hweptemp->ep, &hwreq->req);
993 			spin_lock(hwep->lock);
994 		}
995 	}
996 
997 	if (retval == -EBUSY)
998 		retval = 0;
999 
1000 	return retval;
1001 }
1002 
1003 static int otg_a_alt_hnp_support(struct ci_hdrc *ci)
1004 {
1005 	dev_warn(&ci->gadget.dev,
1006 		"connect the device to an alternate port if you want HNP\n");
1007 	return isr_setup_status_phase(ci);
1008 }
1009 
1010 /**
1011  * isr_setup_packet_handler: setup packet handler
1012  * @ci: UDC descriptor
1013  *
1014  * This function handles setup packet
1015  */
1016 static void isr_setup_packet_handler(struct ci_hdrc *ci)
1017 __releases(ci->lock)
1018 __acquires(ci->lock)
1019 {
1020 	struct ci_hw_ep *hwep = &ci->ci_hw_ep[0];
1021 	struct usb_ctrlrequest req;
1022 	int type, num, dir, err = -EINVAL;
1023 	u8 tmode = 0;
1024 
1025 	/*
1026 	 * Flush data and handshake transactions of previous
1027 	 * setup packet.
1028 	 */
1029 	_ep_nuke(ci->ep0out);
1030 	_ep_nuke(ci->ep0in);
1031 
1032 	/* read_setup_packet */
1033 	do {
1034 		hw_test_and_set_setup_guard(ci);
1035 		memcpy(&req, &hwep->qh.ptr->setup, sizeof(req));
1036 	} while (!hw_test_and_clear_setup_guard(ci));
1037 
1038 	type = req.bRequestType;
1039 
1040 	ci->ep0_dir = (type & USB_DIR_IN) ? TX : RX;
1041 
1042 	switch (req.bRequest) {
1043 	case USB_REQ_CLEAR_FEATURE:
1044 		if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
1045 				le16_to_cpu(req.wValue) ==
1046 				USB_ENDPOINT_HALT) {
1047 			if (req.wLength != 0)
1048 				break;
1049 			num  = le16_to_cpu(req.wIndex);
1050 			dir = (num & USB_ENDPOINT_DIR_MASK) ? TX : RX;
1051 			num &= USB_ENDPOINT_NUMBER_MASK;
1052 			if (dir == TX)
1053 				num += ci->hw_ep_max / 2;
1054 			if (!ci->ci_hw_ep[num].wedge) {
1055 				spin_unlock(&ci->lock);
1056 				err = usb_ep_clear_halt(
1057 					&ci->ci_hw_ep[num].ep);
1058 				spin_lock(&ci->lock);
1059 				if (err)
1060 					break;
1061 			}
1062 			err = isr_setup_status_phase(ci);
1063 		} else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE) &&
1064 				le16_to_cpu(req.wValue) ==
1065 				USB_DEVICE_REMOTE_WAKEUP) {
1066 			if (req.wLength != 0)
1067 				break;
1068 			ci->remote_wakeup = 0;
1069 			err = isr_setup_status_phase(ci);
1070 		} else {
1071 			goto delegate;
1072 		}
1073 		break;
1074 	case USB_REQ_GET_STATUS:
1075 		if ((type != (USB_DIR_IN|USB_RECIP_DEVICE) ||
1076 			le16_to_cpu(req.wIndex) == OTG_STS_SELECTOR) &&
1077 		    type != (USB_DIR_IN|USB_RECIP_ENDPOINT) &&
1078 		    type != (USB_DIR_IN|USB_RECIP_INTERFACE))
1079 			goto delegate;
1080 		if (le16_to_cpu(req.wLength) != 2 ||
1081 		    le16_to_cpu(req.wValue)  != 0)
1082 			break;
1083 		err = isr_get_status_response(ci, &req);
1084 		break;
1085 	case USB_REQ_SET_ADDRESS:
1086 		if (type != (USB_DIR_OUT|USB_RECIP_DEVICE))
1087 			goto delegate;
1088 		if (le16_to_cpu(req.wLength) != 0 ||
1089 		    le16_to_cpu(req.wIndex)  != 0)
1090 			break;
1091 		ci->address = (u8)le16_to_cpu(req.wValue);
1092 		ci->setaddr = true;
1093 		err = isr_setup_status_phase(ci);
1094 		break;
1095 	case USB_REQ_SET_FEATURE:
1096 		if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
1097 				le16_to_cpu(req.wValue) ==
1098 				USB_ENDPOINT_HALT) {
1099 			if (req.wLength != 0)
1100 				break;
1101 			num  = le16_to_cpu(req.wIndex);
1102 			dir = (num & USB_ENDPOINT_DIR_MASK) ? TX : RX;
1103 			num &= USB_ENDPOINT_NUMBER_MASK;
1104 			if (dir == TX)
1105 				num += ci->hw_ep_max / 2;
1106 
1107 			spin_unlock(&ci->lock);
1108 			err = _ep_set_halt(&ci->ci_hw_ep[num].ep, 1, false);
1109 			spin_lock(&ci->lock);
1110 			if (!err)
1111 				isr_setup_status_phase(ci);
1112 		} else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE)) {
1113 			if (req.wLength != 0)
1114 				break;
1115 			switch (le16_to_cpu(req.wValue)) {
1116 			case USB_DEVICE_REMOTE_WAKEUP:
1117 				ci->remote_wakeup = 1;
1118 				err = isr_setup_status_phase(ci);
1119 				break;
1120 			case USB_DEVICE_TEST_MODE:
1121 				tmode = le16_to_cpu(req.wIndex) >> 8;
1122 				switch (tmode) {
1123 				case TEST_J:
1124 				case TEST_K:
1125 				case TEST_SE0_NAK:
1126 				case TEST_PACKET:
1127 				case TEST_FORCE_EN:
1128 					ci->test_mode = tmode;
1129 					err = isr_setup_status_phase(
1130 							ci);
1131 					break;
1132 				default:
1133 					break;
1134 				}
1135 				break;
1136 			case USB_DEVICE_B_HNP_ENABLE:
1137 				if (ci_otg_is_fsm_mode(ci)) {
1138 					ci->gadget.b_hnp_enable = 1;
1139 					err = isr_setup_status_phase(
1140 							ci);
1141 				}
1142 				break;
1143 			case USB_DEVICE_A_ALT_HNP_SUPPORT:
1144 				if (ci_otg_is_fsm_mode(ci))
1145 					err = otg_a_alt_hnp_support(ci);
1146 				break;
1147 			case USB_DEVICE_A_HNP_SUPPORT:
1148 				if (ci_otg_is_fsm_mode(ci)) {
1149 					ci->gadget.a_hnp_support = 1;
1150 					err = isr_setup_status_phase(
1151 							ci);
1152 				}
1153 				break;
1154 			default:
1155 				goto delegate;
1156 			}
1157 		} else {
1158 			goto delegate;
1159 		}
1160 		break;
1161 	default:
1162 delegate:
1163 		if (req.wLength == 0)   /* no data phase */
1164 			ci->ep0_dir = TX;
1165 
1166 		spin_unlock(&ci->lock);
1167 		err = ci->driver->setup(&ci->gadget, &req);
1168 		spin_lock(&ci->lock);
1169 		break;
1170 	}
1171 
1172 	if (err < 0) {
1173 		spin_unlock(&ci->lock);
1174 		if (_ep_set_halt(&hwep->ep, 1, false))
1175 			dev_err(ci->dev, "error: _ep_set_halt\n");
1176 		spin_lock(&ci->lock);
1177 	}
1178 }
1179 
1180 /**
1181  * isr_tr_complete_handler: transaction complete interrupt handler
1182  * @ci: UDC descriptor
1183  *
1184  * This function handles traffic events
1185  */
1186 static void isr_tr_complete_handler(struct ci_hdrc *ci)
1187 __releases(ci->lock)
1188 __acquires(ci->lock)
1189 {
1190 	unsigned i;
1191 	int err;
1192 
1193 	for (i = 0; i < ci->hw_ep_max; i++) {
1194 		struct ci_hw_ep *hwep  = &ci->ci_hw_ep[i];
1195 
1196 		if (hwep->ep.desc == NULL)
1197 			continue;   /* not configured */
1198 
1199 		if (hw_test_and_clear_complete(ci, i)) {
1200 			err = isr_tr_complete_low(hwep);
1201 			if (hwep->type == USB_ENDPOINT_XFER_CONTROL) {
1202 				if (err > 0)   /* needs status phase */
1203 					err = isr_setup_status_phase(ci);
1204 				if (err < 0) {
1205 					spin_unlock(&ci->lock);
1206 					if (_ep_set_halt(&hwep->ep, 1, false))
1207 						dev_err(ci->dev,
1208 						"error: _ep_set_halt\n");
1209 					spin_lock(&ci->lock);
1210 				}
1211 			}
1212 		}
1213 
1214 		/* Only handle setup packet below */
1215 		if (i == 0 &&
1216 			hw_test_and_clear(ci, OP_ENDPTSETUPSTAT, BIT(0)))
1217 			isr_setup_packet_handler(ci);
1218 	}
1219 }
1220 
1221 /******************************************************************************
1222  * ENDPT block
1223  *****************************************************************************/
1224 /**
1225  * ep_enable: configure endpoint, making it usable
1226  *
1227  * Check usb_ep_enable() at "usb_gadget.h" for details
1228  */
1229 static int ep_enable(struct usb_ep *ep,
1230 		     const struct usb_endpoint_descriptor *desc)
1231 {
1232 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1233 	int retval = 0;
1234 	unsigned long flags;
1235 	u32 cap = 0;
1236 
1237 	if (ep == NULL || desc == NULL)
1238 		return -EINVAL;
1239 
1240 	spin_lock_irqsave(hwep->lock, flags);
1241 
1242 	/* only internal SW should enable ctrl endpts */
1243 
1244 	if (!list_empty(&hwep->qh.queue)) {
1245 		dev_warn(hwep->ci->dev, "enabling a non-empty endpoint!\n");
1246 		spin_unlock_irqrestore(hwep->lock, flags);
1247 		return -EBUSY;
1248 	}
1249 
1250 	hwep->ep.desc = desc;
1251 
1252 	hwep->dir  = usb_endpoint_dir_in(desc) ? TX : RX;
1253 	hwep->num  = usb_endpoint_num(desc);
1254 	hwep->type = usb_endpoint_type(desc);
1255 
1256 	hwep->ep.maxpacket = usb_endpoint_maxp(desc);
1257 	hwep->ep.mult = usb_endpoint_maxp_mult(desc);
1258 
1259 	if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
1260 		cap |= QH_IOS;
1261 
1262 	cap |= QH_ZLT;
1263 	cap |= (hwep->ep.maxpacket << __ffs(QH_MAX_PKT)) & QH_MAX_PKT;
1264 	/*
1265 	 * For ISO-TX, we set mult at QH as the largest value, and use
1266 	 * MultO at TD as real mult value.
1267 	 */
1268 	if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == TX)
1269 		cap |= 3 << __ffs(QH_MULT);
1270 
1271 	hwep->qh.ptr->cap = cpu_to_le32(cap);
1272 
1273 	hwep->qh.ptr->td.next |= cpu_to_le32(TD_TERMINATE);   /* needed? */
1274 
1275 	if (hwep->num != 0 && hwep->type == USB_ENDPOINT_XFER_CONTROL) {
1276 		dev_err(hwep->ci->dev, "Set control xfer at non-ep0\n");
1277 		retval = -EINVAL;
1278 	}
1279 
1280 	/*
1281 	 * Enable endpoints in the HW other than ep0 as ep0
1282 	 * is always enabled
1283 	 */
1284 	if (hwep->num)
1285 		retval |= hw_ep_enable(hwep->ci, hwep->num, hwep->dir,
1286 				       hwep->type);
1287 
1288 	spin_unlock_irqrestore(hwep->lock, flags);
1289 	return retval;
1290 }
1291 
1292 /**
1293  * ep_disable: endpoint is no longer usable
1294  *
1295  * Check usb_ep_disable() at "usb_gadget.h" for details
1296  */
1297 static int ep_disable(struct usb_ep *ep)
1298 {
1299 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1300 	int direction, retval = 0;
1301 	unsigned long flags;
1302 
1303 	if (ep == NULL)
1304 		return -EINVAL;
1305 	else if (hwep->ep.desc == NULL)
1306 		return -EBUSY;
1307 
1308 	spin_lock_irqsave(hwep->lock, flags);
1309 
1310 	/* only internal SW should disable ctrl endpts */
1311 
1312 	direction = hwep->dir;
1313 	do {
1314 		retval |= _ep_nuke(hwep);
1315 		retval |= hw_ep_disable(hwep->ci, hwep->num, hwep->dir);
1316 
1317 		if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
1318 			hwep->dir = (hwep->dir == TX) ? RX : TX;
1319 
1320 	} while (hwep->dir != direction);
1321 
1322 	hwep->ep.desc = NULL;
1323 
1324 	spin_unlock_irqrestore(hwep->lock, flags);
1325 	return retval;
1326 }
1327 
1328 /**
1329  * ep_alloc_request: allocate a request object to use with this endpoint
1330  *
1331  * Check usb_ep_alloc_request() at "usb_gadget.h" for details
1332  */
1333 static struct usb_request *ep_alloc_request(struct usb_ep *ep, gfp_t gfp_flags)
1334 {
1335 	struct ci_hw_req *hwreq = NULL;
1336 
1337 	if (ep == NULL)
1338 		return NULL;
1339 
1340 	hwreq = kzalloc(sizeof(struct ci_hw_req), gfp_flags);
1341 	if (hwreq != NULL) {
1342 		INIT_LIST_HEAD(&hwreq->queue);
1343 		INIT_LIST_HEAD(&hwreq->tds);
1344 	}
1345 
1346 	return (hwreq == NULL) ? NULL : &hwreq->req;
1347 }
1348 
1349 /**
1350  * ep_free_request: frees a request object
1351  *
1352  * Check usb_ep_free_request() at "usb_gadget.h" for details
1353  */
1354 static void ep_free_request(struct usb_ep *ep, struct usb_request *req)
1355 {
1356 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1357 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
1358 	struct td_node *node, *tmpnode;
1359 	unsigned long flags;
1360 
1361 	if (ep == NULL || req == NULL) {
1362 		return;
1363 	} else if (!list_empty(&hwreq->queue)) {
1364 		dev_err(hwep->ci->dev, "freeing queued request\n");
1365 		return;
1366 	}
1367 
1368 	spin_lock_irqsave(hwep->lock, flags);
1369 
1370 	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
1371 		dma_pool_free(hwep->td_pool, node->ptr, node->dma);
1372 		list_del_init(&node->td);
1373 		node->ptr = NULL;
1374 		kfree(node);
1375 	}
1376 
1377 	kfree(hwreq);
1378 
1379 	spin_unlock_irqrestore(hwep->lock, flags);
1380 }
1381 
1382 /**
1383  * ep_queue: queues (submits) an I/O request to an endpoint
1384  *
1385  * Check usb_ep_queue()* at usb_gadget.h" for details
1386  */
1387 static int ep_queue(struct usb_ep *ep, struct usb_request *req,
1388 		    gfp_t __maybe_unused gfp_flags)
1389 {
1390 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1391 	int retval = 0;
1392 	unsigned long flags;
1393 
1394 	if (ep == NULL || req == NULL || hwep->ep.desc == NULL)
1395 		return -EINVAL;
1396 
1397 	spin_lock_irqsave(hwep->lock, flags);
1398 	retval = _ep_queue(ep, req, gfp_flags);
1399 	spin_unlock_irqrestore(hwep->lock, flags);
1400 	return retval;
1401 }
1402 
1403 /**
1404  * ep_dequeue: dequeues (cancels, unlinks) an I/O request from an endpoint
1405  *
1406  * Check usb_ep_dequeue() at "usb_gadget.h" for details
1407  */
1408 static int ep_dequeue(struct usb_ep *ep, struct usb_request *req)
1409 {
1410 	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1411 	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
1412 	unsigned long flags;
1413 	struct td_node *node, *tmpnode;
1414 
1415 	if (ep == NULL || req == NULL || hwreq->req.status != -EALREADY ||
1416 		hwep->ep.desc == NULL || list_empty(&hwreq->queue) ||
1417 		list_empty(&hwep->qh.queue))
1418 		return -EINVAL;
1419 
1420 	spin_lock_irqsave(hwep->lock, flags);
1421 
1422 	hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
1423 
1424 	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
1425 		dma_pool_free(hwep->td_pool, node->ptr, node->dma);
1426 		list_del(&node->td);
1427 		kfree(node);
1428 	}
1429 
1430 	/* pop request */
1431 	list_del_init(&hwreq->queue);
1432 
1433 	usb_gadget_unmap_request(&hwep->ci->gadget, req, hwep->dir);
1434 
1435 	req->status = -ECONNRESET;
1436 
1437 	if (hwreq->req.complete != NULL) {
1438 		spin_unlock(hwep->lock);
1439 		usb_gadget_giveback_request(&hwep->ep, &hwreq->req);
1440 		spin_lock(hwep->lock);
1441 	}
1442 
1443 	spin_unlock_irqrestore(hwep->lock, flags);
1444 	return 0;
1445 }
1446 
1447 /**
1448  * ep_set_halt: sets the endpoint halt feature
1449  *
1450  * Check usb_ep_set_halt() at "usb_gadget.h" for details
1451  */
1452 static int ep_set_halt(struct usb_ep *ep, int value)
1453 {
1454 	return _ep_set_halt(ep, value, true);
1455 }
1456 
1457 /**
1458  * ep_set_wedge: sets the halt feature and ignores clear requests
1459  *
1460  * Check usb_ep_set_wedge() at "usb_gadget.h" for details
1461  */
1462 static int ep_set_wedge(struct usb_ep *ep)
1463 {
1464 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1465 	unsigned long flags;
1466 
1467 	if (ep == NULL || hwep->ep.desc == NULL)
1468 		return -EINVAL;
1469 
1470 	spin_lock_irqsave(hwep->lock, flags);
1471 	hwep->wedge = 1;
1472 	spin_unlock_irqrestore(hwep->lock, flags);
1473 
1474 	return usb_ep_set_halt(ep);
1475 }
1476 
1477 /**
1478  * ep_fifo_flush: flushes contents of a fifo
1479  *
1480  * Check usb_ep_fifo_flush() at "usb_gadget.h" for details
1481  */
1482 static void ep_fifo_flush(struct usb_ep *ep)
1483 {
1484 	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1485 	unsigned long flags;
1486 
1487 	if (ep == NULL) {
1488 		dev_err(hwep->ci->dev, "%02X: -EINVAL\n", _usb_addr(hwep));
1489 		return;
1490 	}
1491 
1492 	spin_lock_irqsave(hwep->lock, flags);
1493 
1494 	hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
1495 
1496 	spin_unlock_irqrestore(hwep->lock, flags);
1497 }
1498 
1499 /**
1500  * Endpoint-specific part of the API to the USB controller hardware
1501  * Check "usb_gadget.h" for details
1502  */
1503 static const struct usb_ep_ops usb_ep_ops = {
1504 	.enable	       = ep_enable,
1505 	.disable       = ep_disable,
1506 	.alloc_request = ep_alloc_request,
1507 	.free_request  = ep_free_request,
1508 	.queue	       = ep_queue,
1509 	.dequeue       = ep_dequeue,
1510 	.set_halt      = ep_set_halt,
1511 	.set_wedge     = ep_set_wedge,
1512 	.fifo_flush    = ep_fifo_flush,
1513 };
1514 
1515 /******************************************************************************
1516  * GADGET block
1517  *****************************************************************************/
1518 static int ci_udc_vbus_session(struct usb_gadget *_gadget, int is_active)
1519 {
1520 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1521 	unsigned long flags;
1522 	int gadget_ready = 0;
1523 
1524 	spin_lock_irqsave(&ci->lock, flags);
1525 	ci->vbus_active = is_active;
1526 	if (ci->driver)
1527 		gadget_ready = 1;
1528 	spin_unlock_irqrestore(&ci->lock, flags);
1529 
1530 	if (gadget_ready) {
1531 		if (is_active) {
1532 			pm_runtime_get_sync(&_gadget->dev);
1533 			hw_device_reset(ci);
1534 			hw_device_state(ci, ci->ep0out->qh.dma);
1535 			usb_gadget_set_state(_gadget, USB_STATE_POWERED);
1536 			usb_udc_vbus_handler(_gadget, true);
1537 		} else {
1538 			usb_udc_vbus_handler(_gadget, false);
1539 			if (ci->driver)
1540 				ci->driver->disconnect(&ci->gadget);
1541 			hw_device_state(ci, 0);
1542 			if (ci->platdata->notify_event)
1543 				ci->platdata->notify_event(ci,
1544 				CI_HDRC_CONTROLLER_STOPPED_EVENT);
1545 			_gadget_stop_activity(&ci->gadget);
1546 			pm_runtime_put_sync(&_gadget->dev);
1547 			usb_gadget_set_state(_gadget, USB_STATE_NOTATTACHED);
1548 		}
1549 	}
1550 
1551 	return 0;
1552 }
1553 
1554 static int ci_udc_wakeup(struct usb_gadget *_gadget)
1555 {
1556 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1557 	unsigned long flags;
1558 	int ret = 0;
1559 
1560 	spin_lock_irqsave(&ci->lock, flags);
1561 	if (!ci->remote_wakeup) {
1562 		ret = -EOPNOTSUPP;
1563 		goto out;
1564 	}
1565 	if (!hw_read(ci, OP_PORTSC, PORTSC_SUSP)) {
1566 		ret = -EINVAL;
1567 		goto out;
1568 	}
1569 	hw_write(ci, OP_PORTSC, PORTSC_FPR, PORTSC_FPR);
1570 out:
1571 	spin_unlock_irqrestore(&ci->lock, flags);
1572 	return ret;
1573 }
1574 
1575 static int ci_udc_vbus_draw(struct usb_gadget *_gadget, unsigned ma)
1576 {
1577 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1578 
1579 	if (ci->usb_phy)
1580 		return usb_phy_set_power(ci->usb_phy, ma);
1581 	return -ENOTSUPP;
1582 }
1583 
1584 static int ci_udc_selfpowered(struct usb_gadget *_gadget, int is_on)
1585 {
1586 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1587 	struct ci_hw_ep *hwep = ci->ep0in;
1588 	unsigned long flags;
1589 
1590 	spin_lock_irqsave(hwep->lock, flags);
1591 	_gadget->is_selfpowered = (is_on != 0);
1592 	spin_unlock_irqrestore(hwep->lock, flags);
1593 
1594 	return 0;
1595 }
1596 
1597 /* Change Data+ pullup status
1598  * this func is used by usb_gadget_connect/disconnet
1599  */
1600 static int ci_udc_pullup(struct usb_gadget *_gadget, int is_on)
1601 {
1602 	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1603 
1604 	/*
1605 	 * Data+ pullup controlled by OTG state machine in OTG fsm mode;
1606 	 * and don't touch Data+ in host mode for dual role config.
1607 	 */
1608 	if (ci_otg_is_fsm_mode(ci) || ci->role == CI_ROLE_HOST)
1609 		return 0;
1610 
1611 	pm_runtime_get_sync(&ci->gadget.dev);
1612 	if (is_on)
1613 		hw_write(ci, OP_USBCMD, USBCMD_RS, USBCMD_RS);
1614 	else
1615 		hw_write(ci, OP_USBCMD, USBCMD_RS, 0);
1616 	pm_runtime_put_sync(&ci->gadget.dev);
1617 
1618 	return 0;
1619 }
1620 
1621 static int ci_udc_start(struct usb_gadget *gadget,
1622 			 struct usb_gadget_driver *driver);
1623 static int ci_udc_stop(struct usb_gadget *gadget);
1624 /**
1625  * Device operations part of the API to the USB controller hardware,
1626  * which don't involve endpoints (or i/o)
1627  * Check  "usb_gadget.h" for details
1628  */
1629 static const struct usb_gadget_ops usb_gadget_ops = {
1630 	.vbus_session	= ci_udc_vbus_session,
1631 	.wakeup		= ci_udc_wakeup,
1632 	.set_selfpowered	= ci_udc_selfpowered,
1633 	.pullup		= ci_udc_pullup,
1634 	.vbus_draw	= ci_udc_vbus_draw,
1635 	.udc_start	= ci_udc_start,
1636 	.udc_stop	= ci_udc_stop,
1637 };
1638 
1639 static int init_eps(struct ci_hdrc *ci)
1640 {
1641 	int retval = 0, i, j;
1642 
1643 	for (i = 0; i < ci->hw_ep_max/2; i++)
1644 		for (j = RX; j <= TX; j++) {
1645 			int k = i + j * ci->hw_ep_max/2;
1646 			struct ci_hw_ep *hwep = &ci->ci_hw_ep[k];
1647 
1648 			scnprintf(hwep->name, sizeof(hwep->name), "ep%i%s", i,
1649 					(j == TX)  ? "in" : "out");
1650 
1651 			hwep->ci          = ci;
1652 			hwep->lock         = &ci->lock;
1653 			hwep->td_pool      = ci->td_pool;
1654 
1655 			hwep->ep.name      = hwep->name;
1656 			hwep->ep.ops       = &usb_ep_ops;
1657 
1658 			if (i == 0) {
1659 				hwep->ep.caps.type_control = true;
1660 			} else {
1661 				hwep->ep.caps.type_iso = true;
1662 				hwep->ep.caps.type_bulk = true;
1663 				hwep->ep.caps.type_int = true;
1664 			}
1665 
1666 			if (j == TX)
1667 				hwep->ep.caps.dir_in = true;
1668 			else
1669 				hwep->ep.caps.dir_out = true;
1670 
1671 			/*
1672 			 * for ep0: maxP defined in desc, for other
1673 			 * eps, maxP is set by epautoconfig() called
1674 			 * by gadget layer
1675 			 */
1676 			usb_ep_set_maxpacket_limit(&hwep->ep, (unsigned short)~0);
1677 
1678 			INIT_LIST_HEAD(&hwep->qh.queue);
1679 			hwep->qh.ptr = dma_pool_zalloc(ci->qh_pool, GFP_KERNEL,
1680 						       &hwep->qh.dma);
1681 			if (hwep->qh.ptr == NULL)
1682 				retval = -ENOMEM;
1683 
1684 			/*
1685 			 * set up shorthands for ep0 out and in endpoints,
1686 			 * don't add to gadget's ep_list
1687 			 */
1688 			if (i == 0) {
1689 				if (j == RX)
1690 					ci->ep0out = hwep;
1691 				else
1692 					ci->ep0in = hwep;
1693 
1694 				usb_ep_set_maxpacket_limit(&hwep->ep, CTRL_PAYLOAD_MAX);
1695 				continue;
1696 			}
1697 
1698 			list_add_tail(&hwep->ep.ep_list, &ci->gadget.ep_list);
1699 		}
1700 
1701 	return retval;
1702 }
1703 
1704 static void destroy_eps(struct ci_hdrc *ci)
1705 {
1706 	int i;
1707 
1708 	for (i = 0; i < ci->hw_ep_max; i++) {
1709 		struct ci_hw_ep *hwep = &ci->ci_hw_ep[i];
1710 
1711 		if (hwep->pending_td)
1712 			free_pending_td(hwep);
1713 		dma_pool_free(ci->qh_pool, hwep->qh.ptr, hwep->qh.dma);
1714 	}
1715 }
1716 
1717 /**
1718  * ci_udc_start: register a gadget driver
1719  * @gadget: our gadget
1720  * @driver: the driver being registered
1721  *
1722  * Interrupts are enabled here.
1723  */
1724 static int ci_udc_start(struct usb_gadget *gadget,
1725 			 struct usb_gadget_driver *driver)
1726 {
1727 	struct ci_hdrc *ci = container_of(gadget, struct ci_hdrc, gadget);
1728 	int retval = -ENOMEM;
1729 
1730 	if (driver->disconnect == NULL)
1731 		return -EINVAL;
1732 
1733 
1734 	ci->ep0out->ep.desc = &ctrl_endpt_out_desc;
1735 	retval = usb_ep_enable(&ci->ep0out->ep);
1736 	if (retval)
1737 		return retval;
1738 
1739 	ci->ep0in->ep.desc = &ctrl_endpt_in_desc;
1740 	retval = usb_ep_enable(&ci->ep0in->ep);
1741 	if (retval)
1742 		return retval;
1743 
1744 	ci->driver = driver;
1745 
1746 	/* Start otg fsm for B-device */
1747 	if (ci_otg_is_fsm_mode(ci) && ci->fsm.id) {
1748 		ci_hdrc_otg_fsm_start(ci);
1749 		return retval;
1750 	}
1751 
1752 	pm_runtime_get_sync(&ci->gadget.dev);
1753 	if (ci->vbus_active) {
1754 		hw_device_reset(ci);
1755 	} else {
1756 		usb_udc_vbus_handler(&ci->gadget, false);
1757 		pm_runtime_put_sync(&ci->gadget.dev);
1758 		return retval;
1759 	}
1760 
1761 	retval = hw_device_state(ci, ci->ep0out->qh.dma);
1762 	if (retval)
1763 		pm_runtime_put_sync(&ci->gadget.dev);
1764 
1765 	return retval;
1766 }
1767 
1768 static void ci_udc_stop_for_otg_fsm(struct ci_hdrc *ci)
1769 {
1770 	if (!ci_otg_is_fsm_mode(ci))
1771 		return;
1772 
1773 	mutex_lock(&ci->fsm.lock);
1774 	if (ci->fsm.otg->state == OTG_STATE_A_PERIPHERAL) {
1775 		ci->fsm.a_bidl_adis_tmout = 1;
1776 		ci_hdrc_otg_fsm_start(ci);
1777 	} else if (ci->fsm.otg->state == OTG_STATE_B_PERIPHERAL) {
1778 		ci->fsm.protocol = PROTO_UNDEF;
1779 		ci->fsm.otg->state = OTG_STATE_UNDEFINED;
1780 	}
1781 	mutex_unlock(&ci->fsm.lock);
1782 }
1783 
1784 /**
1785  * ci_udc_stop: unregister a gadget driver
1786  */
1787 static int ci_udc_stop(struct usb_gadget *gadget)
1788 {
1789 	struct ci_hdrc *ci = container_of(gadget, struct ci_hdrc, gadget);
1790 	unsigned long flags;
1791 
1792 	spin_lock_irqsave(&ci->lock, flags);
1793 
1794 	if (ci->vbus_active) {
1795 		hw_device_state(ci, 0);
1796 		spin_unlock_irqrestore(&ci->lock, flags);
1797 		if (ci->platdata->notify_event)
1798 			ci->platdata->notify_event(ci,
1799 			CI_HDRC_CONTROLLER_STOPPED_EVENT);
1800 		_gadget_stop_activity(&ci->gadget);
1801 		spin_lock_irqsave(&ci->lock, flags);
1802 		pm_runtime_put(&ci->gadget.dev);
1803 	}
1804 
1805 	ci->driver = NULL;
1806 	spin_unlock_irqrestore(&ci->lock, flags);
1807 
1808 	ci_udc_stop_for_otg_fsm(ci);
1809 	return 0;
1810 }
1811 
1812 /******************************************************************************
1813  * BUS block
1814  *****************************************************************************/
1815 /**
1816  * udc_irq: ci interrupt handler
1817  *
1818  * This function returns IRQ_HANDLED if the IRQ has been handled
1819  * It locks access to registers
1820  */
1821 static irqreturn_t udc_irq(struct ci_hdrc *ci)
1822 {
1823 	irqreturn_t retval;
1824 	u32 intr;
1825 
1826 	if (ci == NULL)
1827 		return IRQ_HANDLED;
1828 
1829 	spin_lock(&ci->lock);
1830 
1831 	if (ci->platdata->flags & CI_HDRC_REGS_SHARED) {
1832 		if (hw_read(ci, OP_USBMODE, USBMODE_CM) !=
1833 				USBMODE_CM_DC) {
1834 			spin_unlock(&ci->lock);
1835 			return IRQ_NONE;
1836 		}
1837 	}
1838 	intr = hw_test_and_clear_intr_active(ci);
1839 
1840 	if (intr) {
1841 		/* order defines priority - do NOT change it */
1842 		if (USBi_URI & intr)
1843 			isr_reset_handler(ci);
1844 
1845 		if (USBi_PCI & intr) {
1846 			ci->gadget.speed = hw_port_is_high_speed(ci) ?
1847 				USB_SPEED_HIGH : USB_SPEED_FULL;
1848 			if (ci->suspended && ci->driver->resume) {
1849 				spin_unlock(&ci->lock);
1850 				ci->driver->resume(&ci->gadget);
1851 				spin_lock(&ci->lock);
1852 				ci->suspended = 0;
1853 			}
1854 		}
1855 
1856 		if (USBi_UI  & intr)
1857 			isr_tr_complete_handler(ci);
1858 
1859 		if (USBi_SLI & intr) {
1860 			if (ci->gadget.speed != USB_SPEED_UNKNOWN &&
1861 			    ci->driver->suspend) {
1862 				ci->suspended = 1;
1863 				spin_unlock(&ci->lock);
1864 				ci->driver->suspend(&ci->gadget);
1865 				usb_gadget_set_state(&ci->gadget,
1866 						USB_STATE_SUSPENDED);
1867 				spin_lock(&ci->lock);
1868 			}
1869 		}
1870 		retval = IRQ_HANDLED;
1871 	} else {
1872 		retval = IRQ_NONE;
1873 	}
1874 	spin_unlock(&ci->lock);
1875 
1876 	return retval;
1877 }
1878 
1879 /**
1880  * udc_start: initialize gadget role
1881  * @ci: chipidea controller
1882  */
1883 static int udc_start(struct ci_hdrc *ci)
1884 {
1885 	struct device *dev = ci->dev;
1886 	struct usb_otg_caps *otg_caps = &ci->platdata->ci_otg_caps;
1887 	int retval = 0;
1888 
1889 	ci->gadget.ops          = &usb_gadget_ops;
1890 	ci->gadget.speed        = USB_SPEED_UNKNOWN;
1891 	ci->gadget.max_speed    = USB_SPEED_HIGH;
1892 	ci->gadget.name         = ci->platdata->name;
1893 	ci->gadget.otg_caps	= otg_caps;
1894 
1895 	if (ci->is_otg && (otg_caps->hnp_support || otg_caps->srp_support ||
1896 						otg_caps->adp_support))
1897 		ci->gadget.is_otg = 1;
1898 
1899 	INIT_LIST_HEAD(&ci->gadget.ep_list);
1900 
1901 	/* alloc resources */
1902 	ci->qh_pool = dma_pool_create("ci_hw_qh", dev,
1903 				       sizeof(struct ci_hw_qh),
1904 				       64, CI_HDRC_PAGE_SIZE);
1905 	if (ci->qh_pool == NULL)
1906 		return -ENOMEM;
1907 
1908 	ci->td_pool = dma_pool_create("ci_hw_td", dev,
1909 				       sizeof(struct ci_hw_td),
1910 				       64, CI_HDRC_PAGE_SIZE);
1911 	if (ci->td_pool == NULL) {
1912 		retval = -ENOMEM;
1913 		goto free_qh_pool;
1914 	}
1915 
1916 	retval = init_eps(ci);
1917 	if (retval)
1918 		goto free_pools;
1919 
1920 	ci->gadget.ep0 = &ci->ep0in->ep;
1921 
1922 	retval = usb_add_gadget_udc(dev, &ci->gadget);
1923 	if (retval)
1924 		goto destroy_eps;
1925 
1926 	pm_runtime_no_callbacks(&ci->gadget.dev);
1927 	pm_runtime_enable(&ci->gadget.dev);
1928 
1929 	return retval;
1930 
1931 destroy_eps:
1932 	destroy_eps(ci);
1933 free_pools:
1934 	dma_pool_destroy(ci->td_pool);
1935 free_qh_pool:
1936 	dma_pool_destroy(ci->qh_pool);
1937 	return retval;
1938 }
1939 
1940 /**
1941  * ci_hdrc_gadget_destroy: parent remove must call this to remove UDC
1942  *
1943  * No interrupts active, the IRQ has been released
1944  */
1945 void ci_hdrc_gadget_destroy(struct ci_hdrc *ci)
1946 {
1947 	if (!ci->roles[CI_ROLE_GADGET])
1948 		return;
1949 
1950 	usb_del_gadget_udc(&ci->gadget);
1951 
1952 	destroy_eps(ci);
1953 
1954 	dma_pool_destroy(ci->td_pool);
1955 	dma_pool_destroy(ci->qh_pool);
1956 }
1957 
1958 static int udc_id_switch_for_device(struct ci_hdrc *ci)
1959 {
1960 	if (ci->is_otg)
1961 		/* Clear and enable BSV irq */
1962 		hw_write_otgsc(ci, OTGSC_BSVIS | OTGSC_BSVIE,
1963 					OTGSC_BSVIS | OTGSC_BSVIE);
1964 
1965 	return 0;
1966 }
1967 
1968 static void udc_id_switch_for_host(struct ci_hdrc *ci)
1969 {
1970 	/*
1971 	 * host doesn't care B_SESSION_VALID event
1972 	 * so clear and disbale BSV irq
1973 	 */
1974 	if (ci->is_otg)
1975 		hw_write_otgsc(ci, OTGSC_BSVIE | OTGSC_BSVIS, OTGSC_BSVIS);
1976 }
1977 
1978 /**
1979  * ci_hdrc_gadget_init - initialize device related bits
1980  * ci: the controller
1981  *
1982  * This function initializes the gadget, if the device is "device capable".
1983  */
1984 int ci_hdrc_gadget_init(struct ci_hdrc *ci)
1985 {
1986 	struct ci_role_driver *rdrv;
1987 
1988 	if (!hw_read(ci, CAP_DCCPARAMS, DCCPARAMS_DC))
1989 		return -ENXIO;
1990 
1991 	rdrv = devm_kzalloc(ci->dev, sizeof(*rdrv), GFP_KERNEL);
1992 	if (!rdrv)
1993 		return -ENOMEM;
1994 
1995 	rdrv->start	= udc_id_switch_for_device;
1996 	rdrv->stop	= udc_id_switch_for_host;
1997 	rdrv->irq	= udc_irq;
1998 	rdrv->name	= "gadget";
1999 	ci->roles[CI_ROLE_GADGET] = rdrv;
2000 
2001 	return udc_start(ci);
2002 }
2003